A new study published in Science says that the global population could reach 12.3 billion by 2100, an increase of 70 percent over the current population of 7.2 billion.
Fourteen researchers from the United Nations Department of Economic and Social Affairs extrapolated upon UN data to find an 80 percent probability that the global population will rise to between 9.6 billion and 12.3 billion within 100 years.
A 2013 UN population projection using data collected through 2012 predicted a global population of 10.9 billion. However, the researchers behind this new study were skeptical of the 2013 effort’s methodology. In the first study, UN statisticians calculated a range of populations based on whether women worldwide had 0.5 more or fewer children than anticipated and came up with potential populations between 6.2 billion and 15.8 billion.
The 2014 group analyzed the same data but ran population models on a country-by-country basis, accounting for localized trends like ideal family size, education, and access to contraception. The new approach allowed the researchers to say with 95 percent certainty that although growth will likely continue to slow in Asia and South America, Africa’s population alone will swell from 1.1 billion to between 3.1 billion and 5.7 billion.
While such a massive baby boom would tax the planet’s resources, Vaclav Smil, an energy, environment, and food production researcher at the University of Manitoba who is unaffiliated with the study, explained to Wired that population won’t matter as much as “the prevailing levels of consumption.”
Adrian Raftery, a statistician and sociologist at the University of Washington and one of the authers of the new study, told Wired that a “rapidly growing population with [sic] bring challenges, but I think these challenges can be met.”